Paul Graham says Silicon Valley still gives founders an edge that Europe can't fully match. David Paul Morris/Bloomberg via Getty Images Paul Graham says Silicon Valley still beats Stockholm for ambitious founders worldwide. The YC cofounder said Silicon Valley investors move much faster than Europe's startup backers. Paul Graham says Stockholm could one day become Europe's Silicon Valley if these founders return home after. Stockholm has become one of Europe's hottest startup hubs, producing fast-growing AI companies like Lovable, Legora, and Sana Labs. Yet, Paul Graham says ambitious founders should still go to Silicon Valley. "Should I go there?" the Y Combinator cofounder asked during a speech to founders in Sweden last month that was released on video on Wednesday. "Yes, you should. You can go there for a bit and then come back, but you should at least go." Graham's message landed at a moment when Stockholm's startup ecosystem is attracting increasing attention from investors and founders.…